Germicidal lamp mounting and reflector



Oct. 2, 1951 L E 2,569,772

GERMICIDAL LAMP MOUNTING AND REFLECTOR Filed Jan. 13, 1947 IN V EN TOR.

20M BY Q a a! QTTOEN'EY Patented Oct. 2, 1951 GERMICIDAL LAMP MOUNTING AND REFLECTOR Robert E. Olsen,

Venice, Calif.,

assignor to Mitchell Manufacturing 00., Tru-Ad Division, Los Angeles, Calif a corporation of California Application January 13, 1947, Serial No. 721.754

4 Claims.

This invention relates generally to an improved mounting and reflector for longitudinal gaseous discharge lamps, and more specifically, to a germicidal or bactericidal gaseous discharge lamp mounting and reflector adapted to be horizontally mounted on a vertical wall of a room above head height of the average adult, and arranged to emit bactericidal or germicidal radiation in a controlled manner, whereby the optimum bactericidal or germicidal effect is achieved upon the air circulating in the room while the possibility of injury to human occupants of the room from the radiation is avoided.

It is desirable that the radiation emitted from the lamp pass virtually all the way across the room from side to side at an angle slightly above the horizontal. Thus a large portion of the upper region of the room will be traversed by the radiation and virtually all of the rising, warm, bacteria-laden air will pass therethrough and be rendered aseptic thereby. Furthermore, the radiation will be so attenuated by the distance travelled, and will impinge the walls and ceilings at such angles of incidence that virtually none of the radiation will be reflected to the occupants of the room below in sufficient intensity to produce any deleterious or harmful effects.

Generally speaking, the apparatus of this invention comprises a longitudinal" housing open along one side thereof. Parabolically shaped supporting means are mounted within the housing facing the open side thereof and are slightly angularly inclined. A thin sheet reflector is mounted upon and fixed to the parabolically shaped supports whereby said reflector is caused to assume a virtually true parabolic shape. A longitudinal, gaseous, electric discharge lamp is mounted within the parabolically shaped reflector adjacent the focus thereof. Angularly inclined louver means are positioned across at least a portion of the open side of the housing, whereby to reduce the vertical, angular spread of radiation emitted through the open side of the housmg.

Among the many advantages of this construction are the ease of assembly, and the fact that the thin sheet reflector does not have to be manufactured as a true parabola, since it is to be mounted upon and forced into contact with the parabolicall shaped supporting means and thus caused to assume a virtually true parabolic shape. This is a decided advantage over most .prior art constructions which try to manufacture the reflector as a true parabola, this bein exceedingly difiicult and costly to accomplish. The present 2 construction is capable of being hung on a vertical surface above the average height of the occupants of a room so as to direct the rays for the optimum germicidal effect by causing said rays to virtually traverse the upper region of the room at an angle slightly above the horizontal plane and thus avoiding the disadvantages of prior art constructions hereinbefore mentioned. This construction also permits the rapid replacement of the gaseous discharge lamps and the ballast or choke coils and starting relays therefor.

With the above points in mind, it is an object of this invention to provide an improved germicidal lamp mounting and reflector adapted to be mounted upon a vertical wall of a room and to emit germicidal or bactericidal radiation of a controlled, vertical angular spread and mean di rection, whereby the optimum germicidal or bactericidal effect is obtained upon the circulating air in the room while avoiding any deleterious or harmful effects to human occupants of the room.

Other and allied objects will be apparent to those skilled in the art upon a careful examination of the illustrations, specifications, and appended claims. To facilitate understanding, reference will be had to the following drawings of one embodiment of this invention, in which:

Fig. 1 is a perspective view of one embodiment of this invention.

Fig. 2 is a front View, partly broken away, of the apparatus illustrated in Fig. 1 with the louvers removed therefrom and with the gaseous discharge lamp not mounted therein.

Fig. 3 is a sectional View, taken along the plane III-III of Fig. 2.

Fig, 4 is a fragmentary view of a portion of th rear wall of the housing showing one of the mounting slots by which the lamp may be mounted on a vertical surface, such as a wall of a room, or the like. i

More specifically, a longitudinal housing indicated generally at I, is provided with two parallel, end walls, 2 and 3, an upper curved wall 4, a flat back wall 5, and a fiat bottom wall 6. The housing I is provided with an open side indicated generally at l opposite the back wall 5. Mounted within the housing I upon the back wall 5, by suitable fastening means, is a longitudinal base 8 which is slightly upwardly angularly tilted. Mounted upon the tilted base 8 by suitable fastening means, adjacent opposite ends thereof, are two supports, indicated generally at 9 and [0. These supports 9 and 10 are respectively provided with saddle-shaped yokes Ill and l2. Said yokes II and I2 are respectively provided 3 with accurately made, parabolically shaped inner edges l3 and I4. Suitably mounted upon the supports 9 and II! respectively are suitable mounting brackets I5 and I6 adapted to support the upstanding lamp supports I! and [8 respectively. The upstanding lamp supports I! and I8 are adapted "to -both support and make electric contact" withopposed ends of a longitudinal, gaseous discharge tube (not shown) and are well known in the art.

The input A.-C. power line I9, which is externally connected to a source'of alternating current, enters the lamp through a hole 20in the back wall 5 f the housing I and an aperture 2| in the tilted base 8. One of the L L-C. input leads i9 is connected by means'of 'a'conducto'r 22 to one side of a ballast or choke coil indicated generally at 23, the opposite side of which "is connected by a conductor 24 to one electric terminal of the upstanding lamp support and connector 1'1. The other A.-C. input leadl!) is-connected by a conductor 25 to oneelectric terminal 'of theother upstanding lamp support and conhector 18, the other side of which is connected by'aconductor 25 to a starting'relay indicated generally at '21. The other side of the starting relay 2.! 'is connected by a conductor 28 to the ,other terminal of the first mentioned upstanding 'lamp' support andconnector, ll, thus comapletin'g the lamp electric circuit. The choke coil .23 andstarting relay 2? are mounted upon the base 8.

GA thin'sheet reflector '29 is held in contact with the p'arabolically shaped edges 13 and M 0f the supports-B and ill and caused to assume ;a virtually true parabolic shape thereby. Said :thinsheetrefiector is fixed to the supports 9 and ilfljby suitable fasteningmeans, such as screws or'the like, passing through outer-edges-of the thin sheet reflector 29 and 'into theends of the -yokes H and I2 ofthesupports-tand Mat 30. The 'thinsheet reflector is provided with suitable apertures indicated'at ii for allowingwthe ,npstanding lamp supports H and E8 to pass .therethrough so as tobe capableof'mounting a longitudinal, gaseous, discharge lamp (not shown) in front of the parabolic, thin sheet irefiector 29, with -the center line of-the-lamp virtually in line with the focus thereof. Thestarting "relayq2'l 'also-isshown extending throughan aperture 4! -vin the reflector 29. Retaining channels 32 and 33-are fitted over the outer edges-oigthequpper Wall 4 and the lower wall-B of the-housing'i-a'nd pver the pointof-attachment of the outer ejdges of the thin sheet reflector 29 to the ends"of the.

pyokes II; and 12 of th supports9 and-Hl,fso as to pover; same. 'Saicl channelsmay-be fixediin position by suitable screw means or the *like' =livotally mounted at points 34- and '35,; adjacent the lower, outer edge of theend walls 2-and of --t;he -housing -i, is a louverassembly, includ- ,;i ng a plurality of spaced, longitudinally-extendingjouversindicated generally at 36, Sa-idlouver ;;assembly-;includes end plates -tland-se having -parabolically; curved inner surfaces-'arran'ged-tonest within the reflector and against the parabolically curved surfaces thereof so as to hold the lou'vers -in-upwardly inclinedplanes adapted to-reduce the; vertical, angular spread of the ra- -;'diation emitted from thelagnp byremoving-part,;-

19f the lower-portion of the-beam. 'The'endswf the louversabutting the edgesof the; end; walls: 2

gand -3 also act; to position the louver assembly tfi. ,zfi eee ir mve z r th i p e c th douverassembly -36 is a" longitudinal shield 39 4 arranged to shield the gaseous discharge lamp so as to prevent radiation from being emitted directly from the lamp through the open side of the housing not traversed by the louver assembly 3B.

The operation of the device may be described as follows. The lamp is adapted tobe mounted "with theback wall 5 thereof against a vertical surface such as a wall or the like by suitable fastening means, indicated at 40, at a level higher than the head level of the occupants of a room. The tilted ba'se' a acts to effectively rotate the parabolic reflecting surface of the thin sheet reflector29 slightly; upwardly so that the radiation therefrom will beslightly upwardly inclined from the horizontal.

If thegaseousdischarge lamp which is adapted tO'bemounted fb'etween supporting brackets 11 andjfi with the axis thereof in line with the focus of the parabola were a true line source of light, "the radiation emitted from the I parabolically shaped reflector would be true parallel radiation. However, a' gaseous discharge lamp'has .an'appreciable diameter and is not a .true line source of light and therefore the radiation reflected from the reflector 23 through the open s'idel'fof the-housing I will not be true .parallel' radiation, but will diverge slightly, or mother .words,"hav.e a slight angular spread, so .that'the radiation will encompass an increasing vertical distance at increasing horizontal distances from the lamp. It is desirable that the lowerlporltionof this angular spread vin' the radiationbe eliminated so that no deleterious -or harmful effects upon the occupants of the room below the .lampfwill occur.

The louver assemblyafi, when inthe position shown in Figs. 1 and 3, is arrangedto accomplish thisefiect, since radiation directedang'ularly downward either from the gaseouskdischarge lamp directlyorfrom the reflector N -may not pass throughthe upwardly angularly inclined louvers'36, Such radiation is-removedirom the beam of radiation-:emittedfrom the-lamp. However, radiation directed in -a mean .direction slightly above the horizontal 1 may pass: through the louvers -35 virtually unimpeded and lrelatively-non-attenuated. Thus a -portion of kthe vertical angular'spread at the bottom ofithe radiation emitted from" the a lamp has been .effectively eliminated. The-shield 3-9 is so positioned with respect to-.the gaseous discharge lamp as to prevent radiation .-from being emitted directly from the: lamp athrough'the'open side 'i ,of';the

housing not traversed by the louver assembly This is desirablesince otherwise such direct radiation would rise rather abruptly at' too sharp an angle above "the horizontal andbe reflected from thecceiling downward into theroom with HBO.

possibly deleterious or harmful effects te -,-the occupants thereof; M

The louver assembly .36, being pivotally mounted at .34-- and. 35, .may be swungaway from the open side I of the housing I so that the gaseous discharge lamp-maybe readily removed and changed, if desired the; thin .sheet reflector may beremo'vedor changed, ifdesired, and the lamp -startin g re1ay 2'l ballast-:or choke coil.2 3, lamp sup-ports l!: and I 8, or .;various otherportionsof the lamp may readilybe=repaired;.or

changed. After such "repairs or changes the louver assembly 36 maybe swung back intaposition:-and-the:lamp is readyfor-operation. n

' The apparatus is preferably, Qalthoughlnot necessarily, made-ofsheet metal. :Thesurfa-ces of the louver assembly 36 are preferably painted, processed or otherwise treated to render them relatively ray-absorptive and non-reflective. The thin sheet reflector is preferably, although not necessarily, made of aluminum sheet processed by the Alzak process, or otherwise suitably provided with a highly reflective, mirror-like, inner surface. The electric circuit is of standard type including the ballast or choke coil 23 and, starting relay 21 and is adapted to energize a gaseous discharge lamp of the hot cathode type. This functions in a manner well known in the art and need not be specifically described herein.

I claim:

1. A germicidal lamp mounting and reflector comprising: a longitudinal housing open along one side thereof; a longitudinal, tilted base mounted on the inner surface of the housing opposite the open side thereof; a plurality of spaced supports mounted on said tilted base, each of said supports having a parabolically shaped marginal edge facing the open side of the housing and slightly angularly upwardly directed; a thin sheet reflector; means for holding said reflector against the parabolically shaped margins of the supports, whereby said reflector is caused to assume a virtually true parabolic shape; means for mounting a longitudinal gaseous electric discharge lamp within the parabolically shaped reflector adjacent the focus thereof; and a louver assembly including a plurality of longitudinally extending upwardly, angularly, inclined louver means positioned across the lower portion of the open side of the housing whereby to reduce the vertical angular spread of the radiation emitted through the open side of the housing, virtually all of said angular reduction being at the bottomof the beam of radiation, said louver assembly being pivotally connected to the lower portion of the housing and being provided with a shield positioned adjacent the gaseous discharge lamp to intercept radiation emitted from the lamp through the open side of the housing above said louver assembly.

2. In a shielded, longitudinal lamp fixture adapted to be mounted upon a vertical supporting surface, the combination of: a lamp housing including top, back, bottom and end walls and an open front; a louver assembly including a plurality of vertically spaced louver means extending across only the lower portion of said open front in parallel, upwardly inclined planes, the forward edges of said louver being in vertical alignment with the lower forward edge of said housing, said assembly being pivotally connected to the lower front portion of the housing.

3. A lamp fixture of the character stated in claim 2, wherein the louver means in the upper portion of the assembly are wider than those in the lower portion of the assembly.

4. A lamp fixture of the character stated in claim 2 including a shield within said housing substantially parallel to said louver means and disposed above and rearwardly thereof.

ROBERT E. OLSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,900,436 Dourgnon Mar. 7, 1938 1,972,928 Ferrero et a1 Sept. 11, 1934 2,270,680 Glover Jan. 20, 1942 2,316,546 Anderson et al Apr. 13, 1943 2,350,664 Alexander June 6, 1944 2,381,451 Hrabak Aug. 7, 1945 2,423,884 Glass July 15, 1947 FOREIGN PATENTS Number Country Date 494,724 Great Britain Oct. 28, 1938 496,390 Great Britain Nov. 29, 1938 

